Optical systems typically include light sources that exchange light signals with planar optical devices. These optical devices often include one or more waveguides that carry the light signals to and/or from one or more optical components on the optical device. The interface between these waveguides and the light source can often be a source of optical loss in the system because the facet of the light source often must be placed undesirably far from the waveguide facet. Reducing or eliminating the distance between the light source and the waveguide facet can reduce the level of optical loss associated with this interface. Accordingly, there is a need for an improved interface between the waveguide facet and the light source.